The present disclosure relates to a computer and, more particularly, to a computer having a device for guiding and latching an expansion card within the chassis of the computer.
Because of limitations in the useful size of planar circuit boards in computer applications, and in order to provide consumer flexibility, the chassis of the computer, and/or a cage structure within the chassis, are frequently designed to accommodate additional circuit boards, which are referred to as "expansion cards," for peripheral devices to provide additional and/or alternative functionality.
For example, many personal computer circuit boards are designed with standard bus interfaces, such as ISA (Industry Standard Architecture) and EISA (Extended Industry Standard Architecture), into which expansion cards for peripheral devices, such as hard disk controllers, tape controllers, modems and other I/O controllers, may be connected. Thus, a user or service technician may easily add or exchange a peripheral expansion device, such as a modem, by simply adding a new modem card or replacing the old modem card attached to the bus interface with an improved card.
Typically, expansion cards are electrically connected to the circuit board through the use of "female" edge connectors located on the circuit board. These type of connectors contain a number of electrically conductive pins enclosed in a "female" receptacle for receiving a "male" connector portion of the card. This male card portion is designed with contacts corresponding to each pin in the female edge connector, so that when the male card portion is press-fitted into the female receptacle, the corresponding pins of the female edge connector are biased against the respective signal contacts on the male card portion to create a secure electrical connection between the contacts and the connector pins. The female edge connector not only creates a secure electrical connection between the expansion card connector portion and the female edge connector, but also secures the expansion card in place.
However, in these types of designs it is often difficult to manually press-fit an expansion card into its exact position in an edge connector. Also, even if initially press-fitted properly, the card will sometimes move relative to the edge connector, often as a result of an unbalanced weight distribution of components on the card, or due to movement of the computer system, such as in shipping, or the like. Of course, when this movement of the expansion card occurs, contact between the pins in the female edge connector and the contacts on the male connector portion of the card may disengage, causing the card to momentarily, or permanently, lose its electrical connection with the female edge connector. Such electrical disconnects can result in transient or catastrophic faults in the computer system.
Prior art designs have attempted to overcome the above problems by employing card guides and latches on the boards, the chassis, or the cage structure for the cards. The guides usually function to receive one end of the card and guide it into the proper position and the latch is formed separately from the guide and functions to secure the card in the proper position. However, because these guides and latches are formed separately, they are relatively expensive and, in addition, take up valuable circuit board and/or chassis space.
Therefore, what is needed is a guide and latch device for expansion cards in the above described environment which is relatively inexpensive and which occupies relatively little circuit board space.